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D27,999 · Wright · "Design for a Prism-Plate" · Page 1 Home > Prism Glass > Patent Index > Page 1 |
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To all whom it may concern: Be it known that I, FRANK L. WRIGHT, a citizen of the United States, residing at Chicago, in the county of Cook and State of Illinois, have invented a certain new and original Design for Prism-Plates, of which the following is a description. My invention relates to designs for prism-plates. Figure 1 is a plan view of a prism-plate embodying my design. Fig. 2 is a section therethrough. A is the body of the prism-plate; B B, a series of lines of separation on one side thereof, whereby the surface on such side is divided into a series of surface areas C C of substantially uniform size. D D are prisms of a certain angle, as indicated, and forming the field of the prism-plate. E E are a series of prisms of a different angle and arranged so as to form a sort of hollow square intermediate between the center |
and the outer edge of the prism-surface. When considered from the prism
side, the hollow square is formed of prisms of a given angle and the field
both within and without the hollow square is formed of a series of prisms
of a different angle. When viewed from the other side, the field and the
hollow square will differ in appearance, so as to be distinguishable one
from the other. The essential features of my invention are found in a prism-plate comprising a substantially flat extended body with prisms on one side, the prisms having different angles, those of one angle forming a hollow square and those of another angle forming a field within and without the square. I claim-- A design for a prism-plate, substantially as shown and described.
Witnesses: |